[Courses][gimp] Lesson 3: Introduction to Layers and Text

[Carol Spears]

On Fri, Feb 11, 2005 at 12:54:29PM +1100, Mary wrote:
> On Thu, Feb 10, 2005, Patricia Peck wrote:
> > Question:   What is "Export"?  I tried to save "Valentine.jpg", which 
> > may not be the final version, and it told me I had to "export" before it 
> > could be saved as a jpeg.  So I clicked "export", and it apparently 
> > saved, but I don't understand what I did or why some images need this 
> > and some don't.  Is it because it had two layers?
> 
> Yes, essentially. "Export" means "convert to the type of image that can
> be savid in the format you want". JPEGs cannot have multiple layers, so
> before you can save as a JPEG GIMP will 'flatten' all the layers
> together.
> 
> If you open up the image you saved, you'll find that the layers are
> gone. (If you ever want to save in a format which preserves absolutely
> everything, save to the GIMP's own XCF format. Note that the files will
> be enormous though, so you'll definitely want to export before putting
> them on the web!)
> 
one nice thing about learning how to work with graphics with gimp-1.0
is that the export dialog was not very reliable.  it's broken-ness is
really the reason i learned the differences between the file formats and
what each of the different formats wanted (or could handle).

jpegs are actually very simple to handle and more than likely the export
dialog will handle it very well.  gimp-1.0 users will probably still be
Image -->Flatten'ing before saving as jpeg.  the jpeg format wants no
sign of layers or transparency.

using the export dialog to make png's however might cause some trouble.
since the file format can handle transparency it will, whether it is
there or not, making a file larger than is necessary.  there is really
no way for the export dialog to be able to tell if you need that extra
color or not as well, so i dont ever see it being reliable for making
these files efficiently.

carol